Cell Theory Development

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  • Robert Hooke

    Robert Hooke was using a hand made telescope that had a three lens system in which he studied and viewed plants, animals, and non living objects. Hooke was intrested in finding out why a cork could float in water and so he decided to exmaine it. After he cut up tiny slices from a piece of cork, he saw many empty chambers which he called cells.
  • Antoni van Leeuwenhoek

    Using a simple single lens microscope, he was the first to see the movement of a different type of single cells that is now knows as bacteria, sperm etc. Drawing what he had seen through his own small telescope with very thiny lenses, held very close to the eye, he named th cells "animalcules". Since Antoni was so good at making tiny lenses, using light he could create a very high magnification which allowed him to observe the cells structure and movement.
  • Francesco Redi

    Redi questioned the belief that maggots appeared spontanieosuly from raw meat. Redis hypothesis was that the lies that flew around the meet layed thir eggs which made the maggots appear. He tried out an experiment with seeting out three flasks each comtaing the same type of raw meat in it. One with an open top, the second with gauze covering it, and the third had a lid on top. Maggots were found only in the flask open to air and t\he flies that got in accessing them to lay eggs.
  • John Needham

    To prove that things could'nt produce from non-living mtter, John Needham boiled chicken broth in a flask and sealed it. Althogh boiling was considered to kill substances which would make one ill, micro organisms still appeared in the roth. Needham suggested there was a life force that produced spontanious generation.
  • Robert Brown

    Robert Brown identified an important cell structure, the nucleus, as he was studying orcchids. He saw an opaq granular spot within the cell. Brown was not the first to have seen these spots, but was he first to recognize that the cell structure must have some importance for cell functions.
  • M.J. Schleiden and Theodor Schwann

    Schleiden observed that all plants were composed of cells and he proposed that the nucleus was the structure responsible for the development of the remainder of the cell. Schwann believed there must be similarities betwene plant and animal tissues. After searching for answeres, they both proposed that all plants and animals were composed of cells, and that the cell was the basic unit of all organisms, and that cells are produced from pre-existing cells through cell divison, known as Cell Theory.
  • Louis Pasteur

    Using the work of Needham and Spallanzani, Pateur had altered the flask in a very effetive and important way. Before boiling the meat broth in a flask, Pasteur heated the neck of the flask and bent it into an "S" shape. With that type of flask, air could get into the flask, but micro- organisms or particles would get stuck at the bottom of the S bend not affecting the broth. When the flask was tipped so the broth reached the S bend and the opening of the flask, mould appeared in the broth.